The 27-year-old actor has been on a health mission to chisel up

By Jacqueline Andriakos
Updated June 15, 2015 04:10 PM
Credit: Jason Merritt/Getty

Ryan Guzman proved that hard work in the gym really does pay off.

The Boy Next Door actor, 27, shared a shirtless snap on Instagram over the weekend to show off his 21-lb. muscle gain, thanks to three months of serious working out.

“Progress selfie,” he captioned the photo, along with the hashtags, “#3months #21lbsgained #hardwork #TheWorkDoesntStopHere.”

Fans were quick to welcome the six-pack shot, which racked up more than 23,000 likes since he shared it Saturday.

“I think you should be in Magic Mike 3,” one follower commented on the photo, while another wrote, “screen saver!”

Two weeks ago, he posted another wellness-related photo that showed his hand full of what appeared to be vitamins and supplements, with two big containers of protein powder on the counter nearby.

He joked in the caption, “Trying to be healthier but damn I wish these were skittles ”

The actor – who will star in the film Jem and the Holograms in October, and who snagged a role in the NBC mini series Heroes Reborn – is a big believer in staying active and healthy.

He told PEOPLE in January that one of his favorite workouts is Mixed Martial Arts (MMA) training.

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“The MMA training is so intense and so hardcore and so physically demanding that you shed the weight off. It’s incredible,” he said. “I fell in love, not only for that reason, but the mental clarity that I get through my MMA training too.”

But when it comes to his diet, he says, he is blessed with a metabolism that makes it easy to stay fit.

“I know people hate me for saying this, but I really can eat whatever I want because I stay active. If I really want to gain weight, good weight, I have to eat certain proteins and carbs to bring that out,” he explained.